/Engine/Source/Runtime/Core/Public/Misc/MapErrors.h
Landscape proxy {Proxy} had one or more shared properties not in sync with its parent landscape actor {Parent}. This has been fixed but the proxy needs to be saved in order to ensure cooking behaves as expected..
static [FLazyName](API\Runtime\Core\UObject\FLazyName) LandscapeProxyFixupSharedData_Warning;